While answering a question here I googled and found this thief build. It seemed like it was pretty neat so I went into the new character builder and couldn't get a single aspect of that build to work.

I can't seem to select a Vanguard Rapier--even though many different versions of Rapier are there--in fact there seems to be no Vanguard item in the system, but "Vanguard Weapon" still appears in the Compendium for "Any Melee Weapon" with no sign of being deleted/nerfed/altered.

After that I tried the feats they listed, Surprising Charge and Backstabber. Neither feat is listed. I know these are rogue feats but I thought thief was just a specialized rogue build--guess not?

So suddenly I can't figure out if I just don't know how to operate the new web character generator, content has been removed or if I missed something about Essentials classes not being able to use non-essentials feats (Possibly all of the above)

I'd still be using the old/better character generator but after they stopped supporting it it crashed on my system and wouldn't restart.

I'm not complaining about not being able to make some uber-character, I'm just confused as to why the compendium doesn't seem to match up with the CG.

It's also important, in the marketplace, to pay careful attention to the "Show suggested items" box. I had to transfer a character from the old CB to the new CB by hand (thanks, Wizards) and for the life of me I couldn't give him back his weapons. It turned out it was because it wasn't usual for his class, and the "Show suggested items" box was checked, hiding it. That is, the box really means "Suppress unexpected items."

I have noted that with essentials characters the items lists and feats are pared down from what is available.

While this is disappointing (it makes life tough on our mage because he can't add some of the items we find) it does serve a purpose. Essentials characters are designed to be bare bones with limited advancement options. Thus the feat and items lists are paired down. It does however complicate character advancement and item assignment in a campaign with full D&D characters.